I didn’t think I would get such high quality responses here in a row! Starting with low expectations worked out well 😆 I’ve been very satisfied with the sound I’ve been getting from my Rythmik F12G in the med-large room my system is set up within, so I’ve kept putting other upgrades above getting a second one of them. But it’s helpful to get this feedback.
Thankfully, I’ve never had any difficulty integrating subs by ear using manual phase and crossover adjustments. I do have an SVS SB2000 in a different system, so I think I’ll play with trying to integrate it into my main system temporarily, just to see if I can get a general sense of this wild world of sub-bass "smoothness". I have an extra set of longer subwoofer signal cables to make it work, too.